Question and Answers on Angular

Q3: What is a module in Angular?

Q4: What is data binding in Angular?

Q5: What are services in Angular?

Q6: What is dependency injection (DI) in Angular?

Q7: What is Angular CLI?

Q8: What is routing in Angular?

Q9: What are directives in Angular?

Q10: How does Angular handle form validation?

Q11: What is Angular's change detection mechanism?

A11: Angular uses a change detection mechanism to keep the view in sync with the model. It uses a tree of change detectors to detect changes in data and update the DOM accordingly. The default strategy is CheckOnce, which checks for changes when a component's inputs change or an event is triggered.

Q12: What is Angular Ivy?

A12: Ivy is the new rendering engine in Angular that improves the compilation and rendering process. It reduces bundle size, improves performance, and offers better debugging. Ivy became the default engine starting with Angular 9.

Q13: What are Angular pipes?

A13: Pipes are simple functions that accept an input value and return a transformed value. They are used in templates to format data, such as displaying dates or currency in a specific format. Angular includes built-in pipes like DatePipe, CurrencyPipe, and UpperCasePipe.

Q14: How does Angular handle HTTP requests?

A14: Angular uses the HttpClient module to make HTTP requests. This service provides methods to perform HTTP operations like GET, POST, PUT, DELETE, etc. It supports handling responses with RxJS observables, making it easy to work with asynchronous data.

Q15: What is Angular Universal?

A15: Angular Universal is a server-side rendering (SSR) solution for Angular applications. It allows rendering Angular applications on the server, improving performance and SEO by providing fully rendered pages to web crawlers and faster initial loads for users.

Q16: What is lazy loading in Angular?

A16: Lazy loading is a technique in Angular to load feature modules only when they are needed. It helps reduce the initial load time by splitting the application into smaller bundles and loading them on demand. This can be configured using the Angular Router.

Q17: How do you handle forms in Angular?

A17: Angular supports two types of forms: template-driven forms and reactive forms. Template-driven forms are easy to use and suitable for simple forms, while reactive forms offer more control and flexibility, allowing for complex form validation and dynamic form creation.

Q18: What is an Angular guard?

A18: Angular guards are services that control the navigation to or from a route. They implement interfaces like CanActivate, CanDeactivate, Resolve, and CanLoad. Guards are used to protect routes, fetch data before navigation, or prevent users from leaving a route without saving changes.

Q19: What is AOT compilation in Angular?

A19: Ahead-of-Time (AOT) compilation is a process in Angular that compiles the application and templates during the build process, before the browser downloads and runs the code. AOT improves performance by reducing the time the browser needs to render the application.

Q20: What are Angular animations?

A20: Angular animations allow developers to create complex and smooth animations using a native API. Animations are defined in a component's metadata using the @Component decorator. The Angular animation module provides functions like trigger, state, style, animate, and transition to define animations.

Q21: What is the default date format used by the Angular Material Date Picker, and how can I change it to dd/mm/yyyy?

A: The default date format for Angular Material Date Picker is mm/dd/yyyy. To change it to dd/mm/yyyy, you can use Angular's DatePipe to format the date string in your component's TypeScript file. When a user selects a date, format the date using DatePipe and bind the formatted date to your input field.

Q22: How can I use DatePipe to format a date in Angular?

A: First, import DatePipe from @angular/common. Then, use it to transform the date within your component's code. Here's an example of how to format a date to dd/MM/yyyy:

Q23: What role does [value] binding play in changing the date format for an input field in Angular?

A: The [value] binding in Angular is used to bind a variable from the component class to the input field in the template. In this case, it binds the formattedDate variable, which contains the date formatted as dd/mm/yyyy, to the input field. This ensures that the input displays the date in the correct format when a user selects a date from the date picker.